We determine the optimal combination of taxes on money, consumption and income in transactions technology models where exogenous government expenditures must be financed with distortionary taxes. We ...show that the optimal policy does not tax money, regardless of whether the government can use as alternative fiscal instruments an income tax, a consumption tax, or the two taxes jointly. These results are at odds with recent literature. We argue that the reason for this divergence is an inappropriate specification of the transactions technology adopted in the literature.
Radiofrequency ablation (RFA) has become a common treatment of patients with unresectable primary and secondary hepatic malignancies. We performed this prospective analysis to determine early (within ...30 days) and late (more than 30 days after) complication rates associated with hepatic tumor RFA.
All patients treated between January 1, 1996 and June 30, 2002 with RFA for hepatic malignancies were entered into a prospective database. Patients were evaluated during RFA treatment, throughout the immediate post RFA course, and then every 3 months after RFA to assess for the development of treatment-related complications.
A total of 608 patients, 345 men (56.7%) and 263 women (43.3%), with a median age of 58 years (range 18-85 years) underwent RFA of 1225 malignant liver tumors. Open intraoperative RFA was performed in 382 patients (62.8%), while percutaneous RFA was performed in 226 (37.2%). The treatment-related mortality rate was 0.5%. Early complications developed in 43 patients (7.1%). Early complications were more likely to occur in patients treated with open RFA (33 8.6% of 382 patients) compared with percutaneous RFA (10 4.4% 226 patients, P < 0.01), and in patients with cirrhosis (25 12.9% complications in 194 patients) compared with noncirrhotic patients (31 7.5% complications in 414 patients, P < 0.05). Late complications arose in 15 patients (2.4%) with no difference in incidence between open and percutaneous RFA treatment. The combined overall early and late complication rate was 9.5%.
Hepatic tumor RFA can be performed with low mortality and morbidity rates. Though relatively rare, late complications can develop and physicians performing hepatic RFA must be cognizant of these delayed treatment-related problems.
We present an upper limit for the relative escape fraction (f rel esc) of ionizing radiation at z ~ 3.3 using a sample of 11 Lyman break galaxies (LBGs) with deep imaging in the U band obtained with ...the Large Binocular Camera, mounted on the prime focus of the Large Binocular Telescope. We selected 11 LBGs with secure redshifts in the range 3.27 < z < 3.35, from three independent fields. We stacked the images of our sources in the R and U bands, which correspond to an effective rest-frame wavelength of 1500 A and 900 A, respectively, obtaining a limit in the U band image of >=30.7 mag (AB) at 1 Delta *s. We derive a 1 Delta *s upper limit of f rel esc ~ 5%, which is one of the lowest values found in the literature so far at z ~ 3.3. Assuming that the upper limit for the escape fraction that we derived from our sample holds for all galaxies at this redshift, the hydrogen ionization rate that we obtain ( Delta *G--12 < 0.3 s--1) is not enough to keep the intergalactic medium ionized and a substantial contribution to the UV background by faint active galactic nuclei is required. Since our sample is clearly still limited in size, larger z ~ 3 LBG samples at similar or even greater depths are necessary to confirm these results on a more firm statistical basis.
AGN counts at 15$\mu{\rm m} La Franca, F.; Puccetti, S.; Sacchi, N. ...
Astronomy and astrophysics (Berlin),
09/2007, Letnik:
472, Številka:
3
Journal Article
Recenzirano
Context. The counts of galaxies and AGN in the mid infra-red (MIR) bands are important instruments for studying their cosmological evolution. However, the classic spectral line ratios techniques can ...become misleading when trying to properly separate AGN from starbursts or even from apparently normal galaxies. Aims. We use X-ray band observations to discriminate AGN activity in previously classified MIR-selected starburst galaxies and to derive updated AGN1 and (Compton thin) AGN2 counts at 15 \mum. Methods. XMM observations of the ELAIS-S1 15 \mum sample down to flux limits similar to 2\times10 super(-15) erg cm super(-2) s super(-1) (2-10 keV band) were used. We classified as AGN all those MIR sources with a unabsorbed 2-10 keV X-ray luminosity higher that similar to 10 super(42) erg s super(-1). Results. We find that at least about 13\pm6% of the previously classified starburst galaxies harbor an AGN. According to these figures, we provide an updated estimate of the counts of AGN1 and (Compton thin) AGN2 at 15 \mum. It turns out that at least 24% of the extragalactic sources brighter than 0.6 my at 15 \mum are AGN ( similar to 13% contribution to the extragalactic background produced at fluxes brighter than 0.6 mJy).
Background: Oxaliplatin (OXA) and irinotecan (IRI) are active drugs in first-line as well as second-line treatment of advanced colorectal cancer patients, their toxicity profiles are not overlapping, ...and both drugs have shown synergism with folinic acid-modulated 5-fluorouracil (5-FU). We planned this phase I study to define the dose-limiting toxicities (DLTs), the maximum tolerated doses (MTDs), and the recommended doses (RDs) for a triplet regimen including OXA plus IRI on day 1, and 6S-folinic acid (LFA) plus 5-FU on day 2, every 2 weeks. Patients and methods: At least three patients had to be treated at each dose level, and the trial proceeded if no more than 33% of patients showed a DLT after the first cycle. Starting from OXA 85 mg/m2 (over 2 h) and IRI 150 mg/m2 (over 1 h), an alternated escalation was planned up to 110 mg/m2 and 200 mg/m2, respectively. Thereafter, a fixed dose of LFA, 250 mg/m2 (as 2-h infusion), plus an escalating dose of 5-FU (from 650to 800 mg/m2 as an intravenous bolus) was added on day 2 to the previous dose level of OXA and IRI. Results: Forty-six patients, all but four affected by advanced colorectal primaries, entered this study. The MTDs for OXA and IRI given on the same day were 110 and 200 mg/m2: these doses caused a DLT in three of six patients. The previous dose level (110 and 175 mg/m2, respectively) on day 1 was safely followed on day 2 by LFA plus 5-FU up to 800 mg/m2. Indeed, only one of three patients treated at this last level had a DLT. This cohort was then expanded including a total of 14 patients, and on the whole series five cases of DLT occurred: WHO grade 4 neutropenia (two patients), grade 3 or 4 diarrhoea (three patients). Cumulative toxicity was analysed in 43 patients for a total of 347 cycles: grade 4 neutropenia was detected in 13 patients (30%); it was not dose-related, nor was it exacerbated by the addition of modulated 5-FU. Febrile neutropenia occurred in four patients. Grade 3 or 4 diarrhoea was suffered by nine (21%) and five (12%) patients, respectively. Two complete and nine partial responses were reported on 40 evaluable patients (six patients were disease-free at study entry), giving a response rate of 27.5% (95% confidence interval 15% to 44%); nine of 18 (50%) assessable patients of the two last cohorts treated with the triplet regimen achieved a complete response (two patients) or a partial response (seven patients). Conclusions: The RDs for this biweekly regimen were: OXA 110 mg/m2 plus IRI 175 mg/m2 on day 1, and LFA 250 mg/m2 plus 5-FU 800 mg/m2 on day 2. This regimen appeared active in pretreated gastrointestinal malignancies, and it is worthy of being evaluated in advanced colorectal carcinoma after failure of 5-FU-based adjuvant or palliative treatment.
Polarization measurements for the optical counterpart to GRB 020405 are presented and discussed. Our observations were performed with the VLT–UT3 (Melipal) during the second and third night after the ...gamma–ray burst discovery. The polarization degree (and the position angle) appears to be constant between our two observations at a level around $1.5\div2\%$. The polarization can be intrinsic but it is not possible to unambiguously exclude that a substantial fraction of it is induced by dust in the host galaxy.
SUPER Lamperti, I; Harrison, C M; Mainieri, V ...
Astronomy and astrophysics (Berlin),
10/2021, Letnik:
654
Journal Article
Recenzirano
Odprti dostop
We study the impact of active galactic nuclei (AGN) ionised outflows on star formation in high-redshift AGN host galaxies, by combining near-infrared integral field spectroscopic (IFS) observations, ...mapping the Hα emission and O IIIλ5007 outflows, with matched-resolution observations of the rest-frame far-infrared (FIR) emission. We present high-resolution ALMA Band 7 observations of eight X-ray selected AGN (L2 − 10 keV = 1043.8 − 1045.2 erg s−1) at z ∼ 2 from the SUPER (SINFONI Survey for Unveiling the Physics and Effect of Radiative feedback) sample, targeting the observed-frame 870 μm (rest-frame ∼260 μm) continuum at ∼2 kpc (0.2″) spatial resolution. The targets were selected among the SUPER AGN with an O III detection in the IFS maps and with a detection in the FIR photometry. We detected six out of eight targets with signal-to-noise ratio S/N ≳ 10 in the ALMA maps, from which we measured continuum flux densities in the range 0.27 − 2.58 mJy and FIR half-light radii (Re) in the range 0.8 − 2.1 kpc. The other two targets were detected with S/N of 3.6 and 5.9, which are insufficient for spatially resolved analysis. The FIR Re of our sample are comparable to other AGN and star-forming galaxies at a similar redshift from the literature. However, combining our sample with the literature samples, we find that the mean FIR size in X-ray AGN (Re = 1.16 ± 0.11 kpc) is slightly smaller than in non-AGN (Re = 1.69 ± 0.13 kpc). From spectral energy distribution fitting, we find that the main contribution to the 260 μm flux density is dust heated by star formation, with ≤4% contribution from AGN-heated dust and ≤1% from synchrotron emission. The majority of our sample show different morphologies for the FIR (mostly due to reprocessed stellar emission) and the ionised gas emission (Hα and O III, mostly due to AGN emission). This could be due to the different locations of dust and ionised gas, the different sources of the emission (stars and AGN), or the effect of dust obscuration. We are unable to identify any residual Hα emission, above that dominated by AGN, that could be attributed to star formation. Under the assumption that the FIR emission is a reliable tracer of obscured star formation, we find that the obscured star formation activity in these AGN host galaxies is not clearly affected by the ionised outflows. However, we cannot rule out that star formation suppression is happening on smaller spatial scales than the ones we probe with our observations (< 2 kpc) or on different timescales.
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